Nursing Based on Humanistic Care Concept for Continuous Blood Purification for Patients with Severe Sepsis in the Intensive Care Unit.

Context: Mortality from severe sepsis has been declining in recent years but remains a challenge worldwide because it remains the most frequent cause of death in ICUs. High-quality nursing care during a patient's CBP can play an important role in promoting a patient's physical condition. Objective: The study intended to explore the effects of nursing based on a humanistic care concept on continuous blood purification (CBP) treatment for patients with severe sepsis in an intensive care unit (ICU). Design: The research team performed a prospective randomized controlled study. Setting: The study took place at Minhang Hospital at Fudan University in Shanghai, China. Participants: Participants were 80 patients with severe sepsis who had been admitted to the ICU of the hospital and who were receiving CBP between April 2021 and December 2022. Intervention: The research team randomly divided participants into two groups according to their admission sequence, with 40 participants in each group: (1) an intervention group, the humanistic care group, who received CBP under humanistic care, and (2) a control group who received CBP under routine nursing. Outcome Measures: At baseline and postintervention, the research team: (1) measured participants' negative emotions using the Self-rating Anxiety Scale (SAS) and the Self-rating Depression scale (SDS), (2) assessed participants' hope levels using the Herth Hope Index (HHI), and (3) evaluated participants' health statuses using the Acute Physiology and Chronic Health Evaluation (APACHE-II). The team also measured the complication rate and determined participants' treatment compliance. Results: Postintervention compared to the control group, the humanistic care group's: (1) SAS and SDS scores were significantly lower, with P < .001 and P < .001, respectively; (2) HHI score was significantly higher, with P < .001; (3) APACHE-II scores and complication rate were significantly lower, with P < .001 and < .001, respectively; and (4) treatment compliance was significantly higher, with P = .0186. Conclusions: Nursing based on a humanistic care concept in ICUs can effectively alleviate the negative mood of patients with severe sepsis receiving CBP, enhance their hope levels and the treatment effect, improve their health statuses and treatment compliance, and reduce the occurrence of complications.

Huangqi decoction ameliorates kidney injury in db/db mice by regulating the BMP/Smad signaling pathway.

PURPOSE: This study aims to investigate the mechanism underlying the beneficial effects of Huangqi decoction (HQD) on Diabetic kidney disease (DKD) in diabetic db/db mice. METHODS: Eight-week-old male diabetic db/db mice were randomly divided into four groups: Model (1% CMC), HQD-L (0.12 g/kg), HQD-M (0.36 g/kg), and HQD-H (1.08 g/kg) groups. Non-diabetic db/m mice were served as the control group. These mice received HQD treatment for 8 weeks. After treatment, the kidney function, histopathology, micro-assay, and protein expression levels were assessed. RESULTS: HQD treatment improved the albumin/creatine ratio (ACR) and 24 h urinary albumin excretion, prevented the pathological phenotypes of increased glomerular volume, widened mesangial areas, the of mesangial matrix proliferation, foot process effacement, decreased nephrin expression and reduced number of podocytes. Expression profiling analysis revealed global transcriptional changes that predicted related functions, diseases and pathways. HQD treatment activated protein expressions of BMP2, BMP7, BMPR2, and active-Rap1, while inhibiting Smad1 and phospho-ERK. In addition, HQD was associated with improvements in lipid deposition in the kidneys of db/db mice. CONCLUSION: HQD ameliorated the progression of DKD in db/db mice by regulating BMP transcription and downstream targets, inhibiting the phosphorylation of ERK and the expression of Smad1, promoting Rap1 binding to GTP, and regulating the lipid metabolism. These findings provide a potential therapeutic approach for treating DKD.

Phosphorylation-dependent recognition of diverse protein targets by the cryptic GK domain of MAGI MAGUKs.

Dynamic signal transduction requires the rapid assembly and disassembly of signaling complexes, often mediated by phosphoprotein binding modules. The guanylate kinase-like (GK) domain of the membrane-associated guanylate kinases (MAGUKs) is such a module orchestrating signaling at cellular junctions. The MAGI subfamily of MAGUKs contains a truncated GK domain with unknown structure and function, although they participate in diverse physiological and pathological processes. Here, we demonstrate that the truncated GK domain of MAGI2 interacts with its adjacent PDZ0 domain to form a structural supramodule capable of recognizing phosphoproteins. A conserved phosphorylation-dependent binding motif for PDZ0-GK is delineated, which leads to identification of a set of previously unknown binding partners. We explore the structure and function of the MAGI2-target complex with an inhibitory peptide derived from the consensus motif. Our work reveals an action mechanism of the cryptic MAGI GKs and broadens our understanding of the target recognition rules of phosphoprotein binding modules.

Astragaloside IV attenuates high glucose-induced NF-κB-mediated inflammation through activation of PI3K/AKT-ERK-dependent Nrf2/ARE signaling pathway in glomerular mesangial cells.

Inflammation is a key contributor to diabetic kidney disease pathogenesis, including reactive oxidation stress (ROS)-mediated nuclear factor-κB (NF-κB) signaling pathway. In this study, we examined the effect of Astragaloside IV (AS-IV) on anti-inflammatory and anti-oxidative properties under high glucose (HG) condition and the potential mechanism in glomerular mesangial cells (GMCs). We showed that AS-IV concentration-dependently reduced GMCs proliferation, restrained ROS release and hydrogen peroxide content, and suppressed pro-inflammatory cytokines as well as pro-fibrotic factors expression, which were associated with the inhibition of NF-κB and nuclear factor-erythroid 2-related factor 2 (Nrf2) signaling activation. Accordingly, both NF-κB overexpression by using RNA plasmid and Nrf2 gene silencing by using RNA interference weakened the ability of AS-IV to ameliorate HG-induced oxidative stress, inflammation, and cell proliferation. Furthermore, phosphatidylinositide 3-kinases (PI3K)/serine/threonine protein kinase (Akt) and extracellular regulated protein kinases (ERK) signaling pathway regulated the process of AS-IV-induced Nrf2 activation and antioxidant capacity, which evidenced by using PI3K inhibitor LY294002 or ERK inhibitor PD98059 that largely abolished the AS-IV efficacy. Taken together, these results indicated that AS-IV protected against HG-induced GMCs damage by inhibiting ROS/NF-kB-induced increases of inflammatory cytokines, fibrosis biomarkers, and cell proliferation via up-regulation of Nrf2-dependent antioxidant enzyme expression, which were mediated by PI3K/Akt and ERK signaling pathway activation.

Astragaloside IV attenuates podocyte apoptosis through ameliorating mitochondrial dysfunction by up-regulated Nrf2-ARE/TFAM signaling in diabetic kidney disease.

Defective antioxidant system as well as mitochondrial dysfunction contributes to the pathogenesis and progression of diabetic kidney disease (DKD). Nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated signaling is the central defensive mechanism against oxidative stress and therefore pharmacological activation of Nrf2 is a promising therapeutic strategy. In this study, using molecular docking we found that Astragaloside IV (AS-IV), an active ingredient from traditional formula of Huangqi decoction (HQD), exerted a higher potential to promote Nrf2 escape from Keap1-Nrf2 interaction via competitively bind to amino acid sites in Keap1. When podocyte exposed to high glucose (HG) stimulation, mitochondrial morphological alterations and podocyte apoptosis were presented and accompanied by Nrf2 and mitochondrial transcription factor A (TFAM) downregulation. Mechanistically, HG promoted a decrease in mitochondria-specific electron transport chain (ETC) complexes, ATP synthesis and mtDNA content as well as increased ROS production. Conversely, all these mitochondrial defects were dramatically alleviated by AS-IV, but suppression of Nrf2 with inhibitor or siRNA and TFAM siRNA simultaneously alleviated the AS-IV efficacy. Moreover, experimental diabetic mice exhibited significant renal injury as well as mitochondrial disorder, corresponding with the decreased expression of Nrf2 and TFAM. On the contrary, AS-IV reversed the abnormality and the Nrf2 and TFAM expression were also restored. Taken together, the present findings demonstrate the improvement of AS-IV on mitochondrial function, thereby resistance to oxidative stress-induced diabetic kidney injury and podocyte apoptosis, and the process is closely associated with activation of Nrf2-ARE/TFAM signaling.

Zuogui Wan ameliorates high glucose-induced podocyte apoptosis and improves diabetic nephropathy in db/db mice.

Zuogui Wan (ZGW), a well-known traditional Chinese medicine (TCM), has been used to nourish "Kidney-Yin" for a long time in China, implying a protective effect on the kidney. The aim of the present study is to investigate the effect of ZGW on high glucose-induced podocyte apoptosis and diabetic nephropathy (DN) in db/db mice. ZGW (1 g/kg-1/day-1) was administered intragastrically to db/db mice for 8 weeks. HPLC was used for identifying the components of ZGW, biochemical and histopathological approaches were used for evaluating its therapeutic effects, and cultured mouse podocytes were used for further exploring its underlying mechanism in vitro. ZGW improved renal function and podocyte loss and also normalized kidney reactive oxygen species production in db/db mice. The cytotoxicity of ZGW on mouse podocytes was assessed by the LDH assay. The effect of ZGW on podocyte viability and apoptosis was determined with CCK-8 and Annexin-V/PI staining by treatment with high glucose. ZGW attenuated podocyte apoptosis, and oxidative stress was detected by the peroxide-sensitive fluorescent probe 2',7'-dichlorodihydrofluorescein diacetate (DCF-DA) staining in a dose-dependent manner. Furthermore, ZGW decreased the expression of caspase-3 and phospho-p38 in both the kidney cortex and high glucose-treated podocytes. Thus, our data from in vivo and in vitro studies demonstrated that ZGW improved renal injury in diabetes by inhibiting oxidative stress and podocyte apoptosis.

Ultrasound-based radiomics for the evaluation of fetal rat lung maturity: A noninvasive assessment method (Ultrasound-based radiomics in fetal rat lung).

OBJECTIVE: To establish a classification model for the evaluation of rat fetal lung maturity (FLM) using radiomics technology. METHOD: A total of 430 high-throughput features were extracted per fetal lung image from 134 fetal lung ultrasound images (four-cardiac-chamber views) of 67 Sprague-Dawley (SD) fetal rats with a gestational age of 16-21 days. The detection of fetal lung tissues included histopathological staining and the expression of surface proteins SP-A, SP-B, and SP-C. A machine learning classification model was established using a support vector machine based on histopathological results to analyze the relationship between fetal lung texture characteristics and FLM. RESULTS: The rat fetal lungs were divided into two groups: terminal sac period (SD1) and canalicular period (SD2). The mRNA transcription and protein expression level of SP-C protein were significantly higher in the SD1 group than in the SD2 group (p < 0.05). The diagnostic performance of the rat FLM classification model was measured as follows: area under the receiver operating characteristic curve (AUC), 0.93 (training set) and 0.89 (validation set); sensitivity, 89.26% (training set) and 87.10% (validation set); specificity, 85.87% (training set) and 79.17% (validation set); and accuracy, 87.79% (training set) and 83.64% (validation set). CONCLUSION: Ultrasound-based radiomics technology can be used to evaluate the FLM of rats, which lays a foundation for further research on this technology in human fetal lungs.

Serum chromogranin A correlated with albuminuria in diabetic patients and is associated with early diabetic nephropathy.

BACKGROUND: The kidney is the main site for the removal of chromogranin A (CgA). Previous studies have found that patients with renal impairment displayed elevated concentrations of CgA in plasma and that CgA concentrations reflect a deterioration of renal function. In this study, we aimed to estimate serum CgA levels and to evaluate the role of serum CgA in the early diagnosis of diabetic nephropathy (DN). METHODS: A total of 219 patients with type 2 diabetes mellitus (T2DM) were included in this cross-sectional study. These patients were classified into normoalbuminuria (n = 121), microalbuminuria (n = 73), or macroalbuminuria (n = 25) groups based on their urine albumin to creatinine ratios (UACRs). The degree of DN is reflected by UACR. A control group consisted of 45 healthy subjects. The serum CgA levels were measured by ELISA, and other key parameters were assayed. RESULTS: Serum CgA levels were higher in patients with T2DM than in control subjects, and a statistically significant difference among the studied subgroups regarding CgA was found (P < 0.05). The levels of serum CgA increased gradually with the degree of DN (P < 0.001). Serum CgA levels showed a moderate-intensity positive correlation with UACRs (P < 0.001). A cutoff level of 3.46 ng/ml CgA showed 69.86% sensitivity and 66.12% specificity to detect DN in the early stage. CONCLUSION: The levels of serum CgA increased gradually with the degree of DN and can be used as a biomarker in the early detection of DN.

Astragaloside IV prevents endothelial dysfunction by improving oxidative stress in streptozotocin-induced diabetic mouse aortas.

Oxidative stress serves a role in endothelial dysfunction exhibited by patients with diabetes mellitus. Astragaloside IV (AS-IV) is a major active ingredient of Radix Astragali, which is considered to exhibit vasoprotective effects through unknown mechanisms. Thus, the current study was performed to investigate the protective effects of AS-IV in streptozotocin (STZ)-induced endothelial dysfunction and to explore whether antioxidant mechanisms were involved. The protective effects of AS-IV on the endothelium-dependent relaxation and contraction of aortic rings were determined by isometric tension recordings. NADPH subunits and endothelial nitric oxide synthase (eNOS) expression was identified via western blotting. Superoxide dismutase and malondialdehyde levels were assayed using ELISA. Furthermore, the generation of reactive oxygen species (ROS) and nitric oxide (NO) was detected via dihydroethidium and 4,5-diaminofluorescein diacetate staining, respectively. The results revealed that STZ-injected mice exhibited increased aortic endothelium-dependent vasoconstriction and decreased vasorelaxation to acetylcholine. However, AS-IV treatment reversed these effects. NG-nitro-L-arginine was subsequently used to completely inhibit impaired relaxation. Accordingly, impaired NO generation was restored following AS-IV treatment by increasing eNOS phosphorylation levels. Furthermore, ROS formation was also depressed following AS-IV treatment compared with that in STZ-injected mice. AS-IV also decreased the expression of various NADPH subunits, including human neutrophil cytochrome b light chain, neutrophil cytosolic factor 1, NADPH oxidase (NOX)2, NOX4 and Rac-1. The results of the current study may provide novel evidence that diabetes-induced vascular injury arises from either the inhibition of eNOS or the activation of NOX-derived ROS generation. In addition, the results warrant further investigation into the application of AS-IV treatment, leading to the improvement of oxidative stress, in patients with diabetes exhibiting endothelial dysfunction.

Transcriptome-wide association analysis identifies DACH1 as a kidney disease risk gene that contributes to fibrosis.

Genome-wide association studies (GWAS) for kidney function identified hundreds of risk regions; however, the causal variants, target genes, cell types, and disease mechanisms remain poorly understood. Here, we performed transcriptome-wide association studies (TWAS), summary Mendelian randomization, and MetaXcan to identify genes whose expression mediates the genotype effect on the phenotype. Our analyses identified Dachshund homolog 1 (DACH1), a cell-fate determination factor. GWAS risk variant was associated with lower DACH1 expression in human kidney tubules. Human and mouse kidney single-cell open chromatin data (snATAC-Seq) prioritized estimated glomerular filtration rate (eGFR) GWAS variants located on an intronic regulatory region in distal convoluted tubule cells. CRISPR-Cas9-mediated gene editing confirmed the role of risk variants in regulating DACH1 expression. Mice with tubule-specific Dach1 deletion developed more severe renal fibrosis both in folic acid and diabetic kidney injury models. Mice with tubule-specific Dach1 overexpression were protected from folic acid nephropathy. Single-cell RNA sequencing, chromatin immunoprecipitation, and functional analysis indicated that DACH1 controls the expression of cell cycle and myeloid chemotactic factors, contributing to macrophage infiltration and fibrosis development. In summary, integration of GWAS, TWAS, single-cell epigenome, expression analyses, gene editing, and functional validation in different mouse kidney disease models identified DACH1 as a kidney disease risk gene.

DACH1 protects podocytes from experimental diabetic injury and modulates PTIP-H3K4Me3 activity.

Dachshund homolog 1 (DACH1), a key cell-fate determinant, regulates transcription by DNA sequence-specific binding. We identified diminished Dach1 expression in a large-scale screen for mutations that convert injury-resistant podocytes into injury-susceptible podocytes. In diabetic kidney disease (DKD) patients, podocyte DACH1 expression levels are diminished, a condition that strongly correlates with poor clinical outcomes. Global Dach1 KO mice manifest renal hypoplasia and die perinatally. Podocyte-specific Dach1 KO mice, however, maintain normal glomerular architecture at baseline, but rapidly exhibit podocyte injury after diabetes onset. Furthermore, podocyte-specific augmentation of DACH1 expression in mice protects from DKD. Combined RNA sequencing and in silico promoter analysis reveal conversely overlapping glomerular transcriptomic signatures between podocyte-specific Dach1 and Pax transactivation-domain interacting protein (Ptip) KO mice, with upregulated genes possessing higher-than-expected numbers of promoter Dach1-binding sites. PTIP, an essential component of the activating histone H3 lysine 4 trimethylation (H3K4Me3) complex, interacts with DACH1 and is recruited by DACH1 to its promoter-binding sites. DACH1-PTIP recruitment represses transcription and reduces promoter H3K4Me3 levels. DACH1 knockdown in podocytes combined with hyperglycemia triggers target gene upregulation and increases promoter H3K4Me3. These findings reveal that in DKD, diminished DACH1 expression enhances podocyte injury vulnerability via epigenetic derepression of its target genes.

Astragaloside IV inhibits palmitic acid-induced apoptosis through regulation of calcium homeostasis in mice podocytes.

Loss of podocytes is a hallmark of diabetic nephropathy, and a growing body of evidence indicates that podocytes are susceptible to palmitic acid (PA). We have previously shown that AS-IV inhibited PA-induced podocyte apoptosis by activating sarcoendoplasmic reticulum Ca2+ ATPase (SERCA), which indicate calcium regulation may involve in the process. Immunofluorescence staining, Western blot and flow cytometry were used to measure the protective efficacy of AS-IV to ameliorate PA-induced ER stress and podocyte apoptosis. Meanwhile, AS-IV inhibited cytochrome c release, decreased mitochondrial membrane potential, accompany with the depletion of endoplasmic reticulum Ca2+ and elevation of cytosolic and mitochondrial Ca2+. Sequestration of cytosolic calcium with BAPTA-AM limited the response of podocyte apoptosis, while during the process the effect of AS-IV was also restrained. In contrast, elevation of cytosolic calcium with calcium ionophore ionomycin was depressed by AS-IV addition. Furthermore, inhibiting TRPC6 expression with SKF96365 or TRPC6 siRNA counteracted the beneficial effect of AS-IV. Our study provides further evidence to conclude the inhibitory effect of AS-IV to podocyte apoptosis is Ca2+-dependent. And the efficacy correlates with inhibiting TRPC6-mediated Ca2+ influx, and then cellular Ca2+ disturbance was coordinated.

Bi-functional switchable broadband terahertz polarization converter based on a hybrid graphene-metal metasurface.

In this letter, we have proposed a bi-functional switchable broadband polarization converter based on the hybrid graphene-metal metasurface. Turning the bias voltage to change Fermi level Ef from 0 to 1.0 eV, the metasurface can switch between quarter-wave plate (QWP) and half-wave plate (HWP) in the frequency band 1.38-1.72 THz. Besides, the metasurface simultaneously works as a broadband QWP and HWP in different frequency range when Ef = 1.0 eV. In addition, when Ef is in the range of 0.3 eV-0.6 eV, the metasurface can work as bi-functional broadband QWP in different frequencies as well. The physical mechanism of the bi-functional polarization converter can be explained by the electric field amplitude distributions. What's more, we find that the metasurface can work well with a tolerance to the incident light polarization angle of about ± 12.5°, which can also change the converted wave from RHCP to LHCP with the incident polarization angle change of 90°. The hybrid metasurface with the advantages of switchable bi-functions, wide operating bandwidth, and ultra-thin thickness, may achieve potential applications in tunable devices for terahertz communications.

Huangqi decoction inhibits hyperglycemia-induced podocyte apoptosis by down-regulated Nox4/p53/Bax signaling in vitro and in vivo.

BACKGROUND: Podocyte dysfunction is associated with the progression of diabetic nephropathy (DN). Huangqi decoction (HQD), a traditional Chinese medical formula, has been used to improve diabetes-related syndrome in China. The present study was to investigate the protective effect of HQD on podocyte apoptosis and the underlying molecular mechanism. METHODS: Podocyte was used to measure the efficacy of HQD on cell apoptosis, activities of NADPH oxidases, ROS generation and mitochondrial membrane potential (MMP), and the activation of Nox4/p53/Bax signaling pathway with HQD treatment were also investigated in vitro. Renal pathological morphology, renal function, podocyte apoptosis and Nox4/p53/Bax signaling pathway were investigated with STZ-induced diabetic mice in vivo. RESULTS: HQD increased the cell proliferation and MMP level, while the ROS production and activities of NADPH oxidases were decreased. Meanwhile, Nox4/p53/Bax signaling was down-regulated. Contrarily, overexpression of Nox4 or p53 significantly abolished those efficacies of HQD. Accordingly, in vivo study showed that the progressive albuminuria, glomerulosclerosis and loss of podocytes were significantly alleviated with HQD treatment in diabetic mice, which paralleled by the marked inhibition of Nox4/p53/Bax signaling. CONCLUSION: Collectively, we provide further evidence that HQD had a renoprotective effect in preventing podocyte apoptosis, which was mediated at least in part by down-regulation of Nox4/p53/Bax signaling.

Disruption of MAGI2-RapGEF2-Rap1 signaling contributes to podocyte dysfunction in congenital nephrotic syndrome caused by mutations in MAGI2.

The essential role of membrane associated guanylate kinase 2 (MAGI2) in podocytes is indicated by the phenotypes of severe glomerulosclerosis of both MAGI2 knockout mice and in patients with congenital nephrotic syndrome (CNS) caused by mutations in MAGI2. Here, we show that MAGI2 forms a complex with the Rap1 guanine nucleotide exchange factor, RapGEF2, and that this complex is lost when expressing MAGI2 CNS variants. Co-expression of RapGEF2 with wild-type MAGI2, but not MAGI2 CNS variants, enhanced activation of the small GTPase Rap1, a central signaling node in podocytes. In mice, podocyte-specific RapGEF2 deletion resulted in spontaneous glomerulosclerosis, with qualitative glomerular features comparable to MAGI2 knockout mice. Knockdown of RapGEF2 or MAGI2 in human podocytes caused similar reductions in levels of Rap1 activation and Rap1-mediated downstream signaling. Furthermore, human podocytes expressing MAGI2 CNS variants show severe abnormalities of cellular morphology and dramatic loss of actin cytoskeletal organization, features completely rescued by pharmacological activation of Rap1 via a non-MAGI2 dependent upstream pathway. Finally, immunostaining of kidney sections from patients with congenital nephrotic syndrome and MAGI2 mutations showed reduced podocyte Rap1-mediated signaling. Thus, MAGI2-RapGEF2-Rap1 signaling is essential for normal podocyte function. Hence, disruption of this pathway is an important cause of the renal phenotype induced by MAGI2 CNS mutations.

Astragaloside IV protects against podocyte injury via SERCA2-dependent ER stress reduction and AMPKα-regulated autophagy induction in streptozotocin-induced diabetic nephropathy.

Aberrant endoplasmic reticulum (ER) stress and autophagy are associated with diabetic nephropathy. Here we investigated the effect of astragaloside IV (AS-IV) on the progression of diabetic nephropathy (DN) and the underlying mechanism involving ER stress and autophagy in streptozotocin (STZ)-induced diabetic mice and high glucose (HG)-incubated podocytes. The diabetic mice developed progressive albuminuria and glomerulosclerosis within 8 weeks, which were significantly ameliorated by AS-IV treatment in a dose-dependent manner. Moreover, diabetes or HG-induced podocyte apoptosis was markedly attenuated by AS-IV, paralleled by a marked remission in ER stress and a remarkable restoration in impaired autophagy, which were associated with a significant improvement in the expression of sarcoendoplasmic reticulum Ca2+ ATPase 2b (SERCA2b) and AMP-activated protein kinase α (AMPKα) phosphorylation, respectively. Knockdown of SERCA2 in podocytes induced ER stress and largely abolished the protective effect of AS-IV, but had no obvious effect on the expression of autophagy-associated proteins. On the other hand, blockade of either autophagy induction or AMPKα activation could also significantly mitigate AS-IV-induced beneficial effect. Collectively, these results suggest that AS-IV prevented the progression of DN, which is mediated at least in part by SERCA2-dependent ER stress attenuation and AMPKα-promoted autophagy induction.

Huangqi Decoction Ameliorates Streptozotocin-Induced Rat Diabetic Nephropathy through Antioxidant and Regulation of the TGF-ß/MAPK/PPAR-γ Signaling.

BACKGROUND/AIMS: Huangqi Decoction (HQD) has been traditionally used to treat diabetes mellitus in China. The present study was carried out to assess the protective effect of HQD on diabetic nephropathy (DN) using the streptozotocin-induced (STZ) diabetic rats. METHODS: Diabetes was induced by a single intraperitoneal injection of STZ (60 mg/kg) in male Wistar rats. 40 diabetic rats were divided into 5 groups: vehicle-treated (DN group), 0.45, 0.15, 0.05 g/kg HQD-treated diabetic group (HQD group) and 1 mg/kg rosiglitazone-treated diabetic group (RGZ group). 16 normal rats were randomly divided into 2 groups: vehicle-treated normal control group (NC) and 0.45 g/kg HQD-treated normal control group (NC+0.45 g/kg HQD). At the end of 8-week experiment, we measured changes of renal pathological morphology, function, antioxidant enzyme levels and the activation of TGF-ß/PPAR-γ/MAPK signaling pathway. RESULTS: After HQD treatment, renal function, including blood urea nitrogen (BUN), 24-h albuminuria and blood glucose level were improved significantly; meanwhile, impaired kidney redox balance was diminished in diabetic rats. The activation of TGF-ß, phospho-JNK, phospho-p44/42, p47 and p42 phox was blocked and the decrease in PPAR-γ in diabetic rats was attenuated by treatment with HQD in a dose-dependent manner. CONCLUSION: These results suggest that HQD shows therapeutic efficacy in DN characterized by renal dysfunction and pathological changes through hypoglycemic and antioxidant effects.

Calcium Uptake via Mitochondrial Uniporter Contributes to Palmitic Acid-Induced Apoptosis in Mouse Podocytes.

Podocytes are component cells of the glomerular filtration barrier, and their loss by apoptosis is the main cause of proteinuria that leads to diabetic nephropathy (DN). Therefore, insights into podocyte apoptosis mechanism would allow a better understanding of DN pathogenesis and thus help develop adequate therapeutic strategies. Here, we investigated the molecular mechanism of palmitic acid-inhibited cell death in mouse podocytes, and found that palmitic acid increased cell death in a dose- and time-dependent manner. Palmitic acid induces apoptosis in podocytes through upregulation of cytosolic and mitochondrial Ca2+ , mitochondrial membrane potential (MMP), cytochrome c release, and depletion of endoplasmic reticulum (ER) Ca2+ . The intracellular calcium chelator, 1,2-bis (2-aminophenoxy) ethane-N,N,N, N'-tetraacetic acid tetrakis acetoxymethyl ester (BAPTA-AM), partially prevented this upregulation whereas 2-aminoethoxydiphenyl borate (2-APB), an inositol 1,4,5-triphosphate receptor (IP3R) inhibitor; dantrolene, a ryanodine receptor (RyR) inhibitor; and 4,4'-diisothiocyanatostibene-2,2'-disulfonic acid (DIDS), an anion exchange inhibitor, had no effect. Interestingly, ruthenium red and Ru360, both inhibitors of the mitochondrial Ca2+ uniporter (MCU), blocked palmitic acid-induced mitochondrial Ca2+ elevation, cytochrome c release from mitochondria to cytosol, and apoptosis. siRNA to MCU markedly reduced palmitic acid-induced apoptosis. These data indicate that Ca2+ uptake via mitochondrial uniporter contributes to palmitic acid-induced apoptosis in mouse podocytes. J. Cell. Biochem. 118: 2809-2818, 2017. © 2017 Wiley Periodicals, Inc.

Ursodeoxycholic Acid Ameliorated Diabetic Nephropathy by Attenuating Hyperglycemia-Mediated Oxidative Stress.

Oxidative stress has a great role in diabetes and diabetes induced organ damage. Endoplasmic reticulum (ER) stress is involved in the onset of diabetic nephropathy. We hypothesize that ER stress inhibition could protect against kidney injury through anti-oxidative effects. To test whether block ER stress could attenuate oxidative stress and improve diabetic nephropathy in vivo and in vitro, the effect of ursodeoxycholic acid (UDCA), an ER stress inhibitor, on spontaneous diabetic nephropathy db/db mice, ER stress inducer or high glucose-triggered podocytes were studied. Mice were assigned to 3 groups (n=6 per group): control group (treated with vehicle), db/db group (treated with vehicle), and UDCA group (db/db mice treated with 40 mg/kg/d UDCA). After 8 weeks treatment, mice were sacrificed. Blood and kidneys were collected for the assessment of albumin/creatinine ratio, blood urea nitrogen (BUN), serum creatinine (SCr), insulin, total cholesterol, triglyceride, low density lipoprotein cholesterol (LDL-C), oxidized LDL-C, high density lipoprotein cholesterol (HDL-C), non-esterified fatty acid (NEFA), superoxide dismutase (SOD), catalase (CAT), methane dicarboxylic aldehyde (MDA), the expressions of SOD isoforms and glutathione peroxidase 1, as well as histopathological examination. In addition, generation of reactive oxygen species (ROS) was detected by 2'7'-dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescence. The results showed that UDCA alleviated renal ER stress-evoked cell death, oxidative stress, renal dysfunction, ROS production, upregulated the expression of Bcl-2 and suppressed Bax in vivo and in vitro. Hence, inhibition ER stress diminishes oxidative stress and exerts renoprotective effects.

HuangQi Decoction Ameliorates Renal Fibrosis via TGF-ß/Smad Signaling Pathway In Vivo and In Vitro.

OBJECTIVE: Traditional Chinese Medicine compound HuangQi decoction is widely used in clinical treatment of chronic kidney disease, but its role on renal interstitial fibrosis and the underlying mechanism remains unclear. The aim of this study is to investigate the effect of HuangQi decoction on renal interstitial fibrosis and its association with the TGF-ß/Smad signaling pathway Methods: A total of 120 C57/BL mice were randomly divided into six groups: sham group, sham plus high-dose HuangQi decoction (1.08g/kg) group, unilateral ureteral obstruction (UUO) model group, and UUO model plus low to high doses of HuangQi decoction (0.12g/kg, 0.36g/kg and 1.08g/kg respectively) groups. Animals were sacrificed 14 days after the administration and ipsilateral kidney tissue was sampled for pathologic examinations. Immunohistochemistry, PCR and western blot were used to detect the expressions of related molecules in the TGF-ß/Smad signaling pathway. TGF-ß1 was used in in vitro experiments to induce human kidney proximal tubule epithelial cells (HK2). RESULTS: HuangQi decoction improved ipsilateral kidney fibrosis in UUO mice and downregulated the expressions of TGF-ß1, TßRI, TßRII, Smad4, Smad2/3, P-Smad2/3, α-SMA, collagen type I, III and IV in a dose-dependent manner while upregulated the expression of Smad7 in the same fashion. Similar results were found in in vitro studies. CONCLUSION: The protective effect of HuangQi decoction for unilateral ureteral obstruction kidney damage in mice was mediated by downregulating the TGF-ß/Smad signaling pathway.